BRISTOL, Conn.—Connecticut and Massachusetts authorities are searching in and around a lake in the hometown of Aaron Hernandez, the former New England Patriots player who is charged with murder.

Connecticut police referred calls on the nature of Monday's search at Pine Lake in Bristol to Massachusetts prosecutors. Gregg Miliote, a spokesman for the Bristol County district attorney, would not comment.

Hernandez has pleaded not guilty to murder in the death of Odin Lloyd, a 27-year-old Boston semi-professional football player whose body was found June 17 about a mile from Hernandez's home in North Attleborough, Mass. The ex-player's attorneys have called the case against him circumstantial.

Authorities believe Lloyd was killed with a .45-caliber Glock, which hasn't been recovered.